1. Field of the Invention
This invention relates to motorcycles, and particularly to electric motorcycles. In particular, the invention relates to an electric motorcycle having an improved frame with a protected space formed therein.
2. Description of the Background Art
A type of motorcycle is known in which a cast frame structure is used from a viewpoint of reducing the vehicle weight and enhancing the productivity (see Patent Document 1). [Patent Document 1] Japanese Patent No. 3686076
The conventional motorcycle mentioned above has a structure in which the cast frame is opened downward; the upper side of the frame is exposed to the outside to be used as an external appearance part; and the inside of the frame is used as a section for accommodating parts.
Furthermore, if the cast frame is thus exposed as the external appearance design surface, the cast frame needs to be subjected to surface finishing such as coating and plating. If an upper area (straddling section) of the frame, which is easily seen, is exposed to the outside, costs for performing surface finishing on the exposed area tends to become higher, because the external appearance needs to be enhanced in order to maximize visual appeal.
On the other hand, members installed inside the frame need to be accessed from the lower side of the frame, when maintenance of such members is performed. For this reason, a motorcycle having a frame with improved accessibility is needed.